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Fernandes B, Cavaco-Paulo A, Matamá T. A Comprehensive Review of Mammalian Pigmentation: Paving the Way for Innovative Hair Colour-Changing Cosmetics. BIOLOGY 2023; 12:biology12020290. [PMID: 36829566 PMCID: PMC9953601 DOI: 10.3390/biology12020290] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Revised: 01/26/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023]
Abstract
The natural colour of hair shafts is formed at the bulb of hair follicles, and it is coupled to the hair growth cycle. Three critical processes must happen for efficient pigmentation: (1) melanosome biogenesis in neural crest-derived melanocytes, (2) the biochemical synthesis of melanins (melanogenesis) inside melanosomes, and (3) the transfer of melanin granules to surrounding pre-cortical keratinocytes for their incorporation into nascent hair fibres. All these steps are under complex genetic control. The array of natural hair colour shades are ascribed to polymorphisms in several pigmentary genes. A myriad of factors acting via autocrine, paracrine, and endocrine mechanisms also contributes for hair colour diversity. Given the enormous social and cosmetic importance attributed to hair colour, hair dyeing is today a common practice. Nonetheless, the adverse effects of the long-term usage of such cosmetic procedures demand the development of new methods for colour change. In this context, case reports of hair lightening, darkening and repigmentation as a side-effect of the therapeutic usage of many drugs substantiate the possibility to tune hair colour by interfering with the biology of follicular pigmentary units. By scrutinizing mammalian pigmentation, this review pinpoints key targetable processes for the development of innovative cosmetics that can safely change the hair colour from the inside out.
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Affiliation(s)
- Bruno Fernandes
- CEB—Centre of Biological Engineering, University of Minho, Campus of Gualtar, 4710-057 Braga, Portugal
| | - Artur Cavaco-Paulo
- CEB—Centre of Biological Engineering, University of Minho, Campus of Gualtar, 4710-057 Braga, Portugal
- LABBELS—Associate Laboratory, 4710-057 Braga, Portugal
- Correspondence: (A.C.-P.); (T.M.); Tel.: +351-253-604-409 (A.C.-P.); +351-253-601-599 (T.M.)
| | - Teresa Matamá
- CEB—Centre of Biological Engineering, University of Minho, Campus of Gualtar, 4710-057 Braga, Portugal
- LABBELS—Associate Laboratory, 4710-057 Braga, Portugal
- Correspondence: (A.C.-P.); (T.M.); Tel.: +351-253-604-409 (A.C.-P.); +351-253-601-599 (T.M.)
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2
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Population genetic differentiation and genomic signatures of adaptation to climate in an abundant lizard. Heredity (Edinb) 2022; 128:271-278. [PMID: 35277668 PMCID: PMC8987050 DOI: 10.1038/s41437-022-00518-0] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2021] [Revised: 02/15/2022] [Accepted: 02/16/2022] [Indexed: 12/18/2022] Open
Abstract
Species distributed across climatic gradients will typically experience spatial variation in selection, but gene flow can prevent such selection from causing population genetic differentiation and local adaptation. Here, we studied genomic variation of 415 individuals across 34 populations of the common wall lizard (Podarcis muralis) in central Italy. This species is highly abundant throughout this region and populations belong to a single genetic lineage, yet there is extensive phenotypic variation across climatic regimes. We used redundancy analysis to, first, quantify the effect of climate and geography on population genomic variation in this region and, second, to test if climate consistently sorts specific alleles across the landscape. Climate explained 5% of the population genomic variation across the landscape, about half of which was collinear with geography. Linear models and redundancy analyses identified loci that were significantly differentiated across climatic regimes. These loci were distributed across the genome and physically associated with genes putatively involved in thermal tolerance, regulation of temperature-dependent metabolism and reproductive activity, and body colouration. Together, these findings suggest that climate can exercise sufficient selection in lizards to promote genetic differentiation across the landscape in spite of high gene flow.
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Fukuda M. Rab GTPases: Key players in melanosome biogenesis, transport, and transfer. Pigment Cell Melanoma Res 2020; 34:222-235. [PMID: 32997883 DOI: 10.1111/pcmr.12931] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Accepted: 09/23/2020] [Indexed: 12/12/2022]
Abstract
Melanosomes are specialized intracellular organelles that produce and store melanin pigments in melanocytes, which are present in several mammalian tissues and organs, including the skin, hair, and eyes. Melanosomes form and mature stepwise (stages I-IV) in melanocytes and then are transported toward the plasma membrane along the cytoskeleton. They are subsequently transferred to neighboring keratinocytes by a largely unknown mechanism, and incorporated melanosomes are transported to the perinuclear region of the keratinocytes where they form melanin caps. Melanocytes also extend several dendrites that facilitate the efficient transfer of the melanosomes to the keratinocytes. Since the melanosome biogenesis, transport, and transfer steps require multiple membrane trafficking processes, Rab GTPases that are conserved key regulators of membrane traffic in all eukaryotes are crucial for skin and hair pigmentation. Dysfunctions of two Rab isoforms, Rab27A and Rab38, are known to cause a hypopigmentation phenotype in human type 2 Griscelli syndrome patients and in chocolate mice (related to Hermansky-Pudlak syndrome), respectively. In this review article, I review the literature on the functions of each Rab isoform and its upstream and downstream regulators in mammalian melanocytes and keratinocytes.
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Affiliation(s)
- Mitsunori Fukuda
- Laboratory of Membrane Trafficking Mechanisms, Department of Integrative Life Sciences, Graduate School of Life Sciences, Tohoku University, Sendai, Miyagi, Japan
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4
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Hida T, Kamiya T, Kawakami A, Ogino J, Sohma H, Uhara H, Jimbow K. Elucidation of Melanogenesis Cascade for Identifying Pathophysiology and Therapeutic Approach of Pigmentary Disorders and Melanoma. Int J Mol Sci 2020; 21:ijms21176129. [PMID: 32854423 PMCID: PMC7503925 DOI: 10.3390/ijms21176129] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/02/2020] [Revised: 08/22/2020] [Accepted: 08/22/2020] [Indexed: 12/15/2022] Open
Abstract
Melanogenesis is the biological and biochemical process of melanin and melanosome biosynthesis. Melanin is formed by enzymic reactions of tyrosinase family proteins that convert tyrosine to form brown-black eumelanin and yellow-red pheomelanin within melanosomal compartments in melanocytes, following the cascades of events interacting with a series of autocrine and paracrine signals. Fully melanized melanosomes are delivered to keratinocytes of the skin and hair. The symbiotic relation of a melanocyte and an associated pool of keratinocytes is called epidermal melanin unit (EMU). Microphthalmia-associated transcription factor (MITF) plays a vital role in melanocyte development and differentiation. MITF regulates expression of numerous pigmentation genes for promoting melanocyte differentiation, as well as fundamental genes for maintaining cell homeostasis. Diseases involving alterations of EMU show various forms of pigmentation phenotypes. This review introduces four major topics of melanogenesis cascade that include (1) melanocyte development and differentiation, (2) melanogenesis and intracellular trafficking for melanosome biosynthesis, (3) melanin pigmentation and pigment-type switching, and (4) development of a novel therapeutic approach for malignant melanoma by elucidation of melanogenesis cascade.
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Affiliation(s)
- Tokimasa Hida
- Department of Dermatology, Sapporo Medical University School of Medicine, Sapporo 060-8543, Hokkaido, Japan; (T.H.); (T.K.); (H.U.)
| | - Takafumi Kamiya
- Department of Dermatology, Sapporo Medical University School of Medicine, Sapporo 060-8543, Hokkaido, Japan; (T.H.); (T.K.); (H.U.)
| | - Akinori Kawakami
- Cutaneous Biology Research Center, Department of Dermatology, Massachusetts General Hospital, Harvard Medical School, Charlestown, MA 02129, USA;
| | - Jiro Ogino
- Department of Pathology, JR Sapporo Hospital, Sapporo 060-0033, Hokkaido, Japan;
| | - Hitoshi Sohma
- Department of Biomedical Engineering, Sapporo Medical University School of Medicine, Sapporo 060-8556, Hokkaido, Japan;
| | - Hisashi Uhara
- Department of Dermatology, Sapporo Medical University School of Medicine, Sapporo 060-8543, Hokkaido, Japan; (T.H.); (T.K.); (H.U.)
| | - Kowichi Jimbow
- Institute of Dermatology & Cutaneous Sciences, Sapporo 060-0042, Hokkaido, Japan
- Correspondence: ; Tel.: +81-11-887-8266
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5
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Crawford M, Liu N, Mahdipour E, Barr K, Heit B, Dagnino L. Integrin-linked kinase regulates melanosome trafficking and melanin transfer in melanocytes. Mol Biol Cell 2020; 31:768-781. [PMID: 32049584 PMCID: PMC7185957 DOI: 10.1091/mbc.e19-09-0510] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
Melanosomes are melanin-containing organelles that provide pigmentation and protection from solar UV radiation to the skin. In melanocytes, melanosomes mature and traffic to dendritic tips, where they are transferred to adjacent epidermal keratinocytes through pathways that involve microtubule networks and the actin cytoskeleton. However, the role of scaffold proteins in these processes is poorly understood. Integrin-linked kinase (ILK) is a scaffold protein that regulates microtubule stability and F-actin dynamics. Here we show that ILK is necessary for normal trafficking of melanosomes along microtubule tracks. In the absence of ILK, immature melanosomes are not retained in perinuclear regions, and mature melanosome trafficking along microtubule tracks is impaired. These deficits can be attenuated by microtubule stabilization. Microtubules are also necessary for the formation of dendrites in melanocytes, and Ilk inactivation reduces melanocyte dendricity. Activation of glycogen synthase kinase-3 (GSK-3) interferes with microtubule assembly. Significantly, inhibition of GSK-3 activity or exogenous expression of the GSK-3 substrate collapsin response mediator protein 2 (CRMP2) in ILK-deficient melanocytes restored dendricity. ILK is also required for normal melanin transfer, and GSK-3 inhibition in melanocytes partially restored melanin transfer to neighboring keratinocytes. Thus, our work shows that ILK is a central modulator of melanosome movements in primary epidermal melanocytes and identifies ILK and GSK-3 as important modulators of melanin transfer to keratinocytes, a key process for epidermal UV photoprotection.
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Affiliation(s)
- Melissa Crawford
- Department of Physiology and Pharmacology, Children's Health Research Institute and Lawson Health Research Institute, University of Western Ontario, London, ON N6G 2C4, Canada
| | - Nancy Liu
- Department of Physiology and Pharmacology, Children's Health Research Institute and Lawson Health Research Institute, University of Western Ontario, London, ON N6G 2C4, Canada
| | - Elahe Mahdipour
- Department of Physiology and Pharmacology, Children's Health Research Institute and Lawson Health Research Institute, University of Western Ontario, London, ON N6G 2C4, Canada.,Department of Medical Biotechnology and Nanotechnology, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Kevin Barr
- Department of Physiology and Pharmacology, Children's Health Research Institute and Lawson Health Research Institute, University of Western Ontario, London, ON N6G 2C4, Canada
| | - Bryan Heit
- Department of Microbiology and Immunology and Robarts Research Institute, University of Western Ontario, London, ON N6G 2C4, Canada
| | - Lina Dagnino
- Department of Physiology and Pharmacology, Children's Health Research Institute and Lawson Health Research Institute, University of Western Ontario, London, ON N6G 2C4, Canada.,Department of Oncology, University of Western Ontario, London, ON N6G 2C4, Canada
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6
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Solano F. On the Metal Cofactor in the Tyrosinase Family. Int J Mol Sci 2018; 19:ijms19020633. [PMID: 29473882 PMCID: PMC5855855 DOI: 10.3390/ijms19020633] [Citation(s) in RCA: 53] [Impact Index Per Article: 8.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2018] [Revised: 02/13/2018] [Accepted: 02/13/2018] [Indexed: 12/16/2022] Open
Abstract
The production of pigment in mammalian melanocytes requires the contribution of at least three melanogenic enzymes, tyrosinase and two other accessory enzymes called the tyrosinase-related proteins (Trp1 and Trp2), which regulate the type and amount of melanin. The last two proteins are paralogues to tyrosinase, and they appeared late in evolution by triplication of the tyrosinase gene. Tyrosinase is a copper-enzyme, and Trp2 is a zinc-enzyme. Trp1 has been more elusive, and the direct identification of its metal cofactor has never been achieved. However, due to its enzymatic activity and similarities with tyrosinase, it has been assumed as a copper-enzyme. Recently, recombinant human tyrosinase and Trp1 have been expressed in enough amounts to achieve for the first time their crystallization. Unexpectedly, it has been found that Trp1 contains a couple of Zn(II) at the active site. This review discusses data about the metal cofactor of tyrosinase and Trps. It points out differences in the studied models, and it proposes some possible points accounting for the apparent discrepancies currently appearing. Moreover, some proposals about the possible flexibility of the tyrosinase family to uptake copper or zinc are discussed.
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Affiliation(s)
- Francisco Solano
- Department Biochemistry and Molecular Biology B and Immunology, School of Medicine and LAIB-IMIB, University of Murcia, 30100 Murcia, Spain.
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7
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Alonso-Curbelo D, Riveiro-Falkenbach E, Pérez-Guijarro E, Cifdaloz M, Karras P, Osterloh L, Megías D, Cañón E, Calvo TG, Olmeda D, Gómez-López G, Graña O, Sánchez-Arévalo Lobo VJ, Pisano DG, Wang HW, Ortiz-Romero P, Tormo D, Hoek K, Rodríguez-Peralto JL, Joyce JA, Soengas MS. RAB7 controls melanoma progression by exploiting a lineage-specific wiring of the endolysosomal pathway. Cancer Cell 2014; 26:61-76. [PMID: 24981740 DOI: 10.1016/j.ccr.2014.04.030] [Citation(s) in RCA: 75] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Revised: 03/13/2014] [Accepted: 04/28/2014] [Indexed: 12/20/2022]
Abstract
Although common cancer hallmarks are well established, lineage-restricted oncogenes remain less understood. Here, we report an inherent dependency of melanoma cells on the small GTPase RAB7, identified within a lysosomal gene cluster that distinguishes this malignancy from over 35 tumor types. Analyses in human cells, clinical specimens, and mouse models demonstrated that RAB7 is an early-induced melanoma driver whose levels can be tuned to favor tumor invasion, ultimately defining metastatic risk. Importantly, RAB7 levels and function were independent of MITF, the best-characterized melanocyte lineage-specific transcription factor. Instead, we describe the neuroectodermal master modulator SOX10 and the oncogene MYC as RAB7 regulators. These results reveal a unique wiring of the lysosomal pathway that melanomas exploit to foster tumor progression.
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Affiliation(s)
- Direna Alonso-Curbelo
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Erica Riveiro-Falkenbach
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Eva Pérez-Guijarro
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Metehan Cifdaloz
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Panagiotis Karras
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Lisa Osterloh
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Diego Megías
- Confocal Microscopy Unit, Biotechnology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Estela Cañón
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Tonantzin G Calvo
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - David Olmeda
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Gonzalo Gómez-López
- Bioinformatics Unit, Structural Biology and Biocomputing Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Osvaldo Graña
- Bioinformatics Unit, Structural Biology and Biocomputing Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Víctor Javier Sánchez-Arévalo Lobo
- Epithelial Carcinogenesis Laboratory, Molecular Pathology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - David G Pisano
- Bioinformatics Unit, Structural Biology and Biocomputing Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Hao-Wei Wang
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - Pablo Ortiz-Romero
- Instituto de Investigación i+12, Hospital 12 de Octubre, Universidad Complutense, Madrid 28041, Spain
| | - Damià Tormo
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain
| | - Keith Hoek
- Department of Dermatology, University Hospital of Zurich, Zurich 8091, Switzerland
| | - José L Rodríguez-Peralto
- Instituto de Investigación i+12, Hospital 12 de Octubre, Universidad Complutense, Madrid 28041, Spain
| | - Johanna A Joyce
- Cancer Biology and Genetics Program, Memorial Sloan Kettering Cancer Center, New York, NY 10065, USA
| | - María S Soengas
- Melanoma Laboratory, Molecular Oncology Programme, Spanish National Cancer Research Centre (CNIO), Madrid 28029, Spain.
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8
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Ambrosio AL, Boyle JA, Di Pietro SM. Mechanism of platelet dense granule biogenesis: study of cargo transport and function of Rab32 and Rab38 in a model system. Blood 2012; 120:4072-81. [PMID: 22927249 PMCID: PMC3496959 DOI: 10.1182/blood-2012-04-420745] [Citation(s) in RCA: 74] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2012] [Accepted: 08/12/2012] [Indexed: 12/21/2022] Open
Abstract
Dense granules are important in platelet aggregation to form a hemostatic plug as evidenced by the increased bleeding time in mice and humans with dense granule deficiency. Dense granules also are targeted by antiplatelet agents because of their role in thrombus formation. Therefore, the molecular understanding of the dense granule and its biogenesis is of vital importance. In this work, we establish a human megakaryocytic cell line (MEG-01) as a model system for the study of dense granule biogenesis using a variety of cell biology and biochemical approaches. Using this model system, we determine the late endocytic origin of these organelles by colocalization of the internalized fluid phase marker dextran with both mepacrine and transmembrane dense granule proteins. By mistargeting of mutant dense granule proteins, we demonstrate that sorting signals recognized by adaptor protein-3 are necessary for normal transport to dense granules. Furthermore, we show that tissue-specific Rab32 and Rab38 are crucial for the fusion of vesicles containing dense granule cargo with the maturing organelle. This work sheds light on the biogenesis of dense granules at the molecular level and opens the possibility of using this powerful model system for the investigation of new components of the biogenesis machinery.
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Affiliation(s)
- Andrea L Ambrosio
- Department of Biochemistry and Molecular Biology, Colorado State University, Fort Collins, CO 80523-1870, USA
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9
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Tyrosinase related protein 1 (TYRP1/gp75) in human cutaneous melanoma. Mol Oncol 2011; 5:150-5. [PMID: 21324755 DOI: 10.1016/j.molonc.2011.01.006] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2010] [Accepted: 01/27/2011] [Indexed: 02/06/2023] Open
Abstract
Melanoma prognosis is based on specific pathological features at the primary lesion. In metastatic patients, the extent of lymph node involvement is also an important prognosis indicator. Many progression markers both in tissues and serum, including circulating tumor cells, have been studied and new molecular markers are awaited from high-throughput screenings to discriminate between clinical stages and predict disease progression. The present review focuses on human tyrosinase related protein 1 also known as gp75 glycoprotein (Tyrp1/gp75), a melanosomal protein involved in the pigmentary machinery of the melanocyte and often used as differentiation marker, with a special emphasis on its emerging roles in the malignant melanocyte and melanoma progression.
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Hida T, Sohma H, Kokai Y, Kawakami A, Hirosaki K, Okura M, Tosa N, Yamashita T, Jimbow K. Rab7 is a critical mediator in vesicular transport of tyrosinase-related protein 1 in melanocytes. J Dermatol 2010; 38:432-41. [PMID: 21352276 DOI: 10.1111/j.1346-8138.2010.01004.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
How melanosomal proteins such as enzymic proteins (tyrosinase and tyrosinase-related proteins, Tyrps) and structural protein (gp100) are transported from Golgi to melanosomal compartments is not yet fully understood. A number of small GTPases have been found to be associated with melanosomes and we have identified one of them, Rab7, a regulator of vesicular transport, organelle motility, phospholipid signaling and cytosolic degradative machinery, as being involved in the transport of Tyrp1 from Golgi to stage I melanosomes. This study further characterizes the role of Rab7 as a regulator of differential sorting of melanosomal proteins in this process. Murine melanocytes were transiently transfected with a plasmid encoding either wild-type (Rab7WT), constitutively active (Rab7Q67L) or dominant-negative (Rab7N125I and Rab7T22N) Rab7. Through immunocytostaining and confocal laser scanning microscopy, we quantitatively compared the bio-distribution of melanosomal proteins between Rab7WT-expressing cells and mutant Rab7-expressing cells. We also characterized their differential elimination from melanosomal compartments by Rab7 by utilizing a proteasome inhibitor, MG132. Our findings indicate that Rab7 plays an important role in differential sorting of tyrosinase, Tyrp1 and gp100 in early melanogenesis cascade, and that it is more specifically involved with Tyrp1 than tyrosinase and gp100 in the trafficking from Golgi to melanosomes and the specific exit from the degradative process.
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Affiliation(s)
- Tokimasa Hida
- Department of Dermatology, Sapporo Medical University School of Medicine, Sapporo, Japan
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11
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Vachtenheim J, Borovanský J. “Transcription physiology” of pigment formation in melanocytes: central role of MITF. Exp Dermatol 2010; 19:617-27. [PMID: 20201954 DOI: 10.1111/j.1600-0625.2009.01053.x] [Citation(s) in RCA: 263] [Impact Index Per Article: 18.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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12
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Truschel ST, Simoes S, Setty SRG, Harper DC, Tenza D, Thomas PC, Herman KE, Sackett SD, Cowan DC, Theos AC, Raposo G, Marks MS. ESCRT-I function is required for Tyrp1 transport from early endosomes to the melanosome limiting membrane. Traffic 2009; 10:1318-36. [PMID: 19624486 DOI: 10.1111/j.1600-0854.2009.00955.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Melanosomes are lysosome-related organelles that coexist with lysosomes within melanocytes. The pathways by which melanosomal proteins are diverted from endocytic organelles toward melanosomes are incompletely defined. In melanocytes from mouse models of Hermansky-Pudlak syndrome that lack BLOC-1, melanosomal proteins such as tyrosinase-related protein 1 (Tyrp1) accumulate in early endosomes. Whether this accumulation represents an anomalous pathway or an arrested normal intermediate in melanosome protein trafficking is not clear. Here, we show that early endosomes are requisite intermediates in the trafficking of Tyrp1 from the Golgi to late stage melanosomes in normal melanocytic cells. Kinetic analyses show that very little newly synthesized Tyrp1 traverses the cell surface and that internalized Tyrp1 is inefficiently sorted to melanosomes. Nevertheless, nearly all Tyrp1 traverse early endosomes since it becomes trapped within enlarged, modified endosomes upon overexpression of Hrs. Although Tyrp1 localization is not affected by Hrs depletion, depletion of the ESCRT-I component, Tsg101, or inhibition of ESCRT function by dominant-negative approaches results in a dramatic redistribution of Tyrp1 to aberrant endosomal membranes that are largely distinct from those harboring traditional ESCRT-dependent, ubiquitylated cargoes such as MART-1. The lysosomal protein content of some of these membranes and the lack of Tyrp1 recycling to the plasma membrane in Tsg101-depleted cells suggests that ESCRT-I functions downstream of BLOC-1. Our data delineate a novel pathway for Tyrp1 trafficking and illustrate a requirement for ESCRT-I function in controlling protein sorting from vacuolar endosomes to the limiting membrane of a lysosome-related organelle.
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Affiliation(s)
- Steven T Truschel
- Department of Pathology and Laboratory Medicine, University of Pennsylvania, Philadelphia, PA 19104, USA
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Kawakami A, Sakane F, Imai SI, Yasuda S, Kai M, Kanoh H, Jin HY, Hirosaki K, Yamashita T, Fisher DE, Jimbow K. Rab7 regulates maturation of melanosomal matrix protein gp100/Pmel17/Silv. J Invest Dermatol 2008; 128:143-50. [PMID: 17625594 DOI: 10.1038/sj.jid.5700964] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022]
Abstract
Melanosome biogenesis consists of multistep processes that involve synthesis of melanosomal protein, which is followed by vesicle transport/fusion and post-translational modifications such as glycosylation, proteolysis, and oligomerization. Because of its complexity, the details of the molecular mechanism of melanosome biogenesis are not yet fully understood. Here, we report that, in MMAc melanoma cells, wild-type (WT) Rab7 and its dominant-active mutant (Rab7-Q67L), but not its dominant-negative mutant (Rab7-T22N), were colocalized in the perinuclear region with granules containing Stage I melanosomes, where the full-length, immature gp100/Pmel17/Silv was present. It was also found that overexpression of Rab7-Q67L and, to a lesser extent, Rab7-WT increased the amount of proteolytically processed, mature gp100. However, Rab7-T22N did not show such an effect. Moreover, siRNA-mediated Rab7 knockdown considerably inhibited gp100 maturation. These results collectively suggest that the GTP-bound form of Rab7 promotes melanogenesis through the regulation of gp100 maturation in melanoma cells.
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Affiliation(s)
- Akinori Kawakami
- Department of Dermatology, Sapporo Medical University School of Medicine, Sapporo, Japan
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14
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Shah AH, Cianciola NL, Mills JL, Sönnichsen FD, Carlin C. Adenovirus RIDalpha regulates endosome maturation by mimicking GTP-Rab7. ACTA ACUST UNITED AC 2007; 179:965-80. [PMID: 18039930 PMCID: PMC2099200 DOI: 10.1083/jcb.200702187] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
The small guanosine triphosphatase Rab7 regulates late endocytic trafficking. Rab7-interacting lysosomal protein (RILP) and oxysterol-binding protein-related protein 1L (ORP1L) are guanosine triphosphate (GTP)-Rab7 effectors that instigate minus end-directed microtubule transport. We demonstrate that RILP and ORP1L both interact with the group C adenovirus protein known as receptor internalization and degradation alpha (RIDalpha), which was previously shown to clear the cell surface of several membrane proteins, including the epidermal growth factor receptor and Fas (Carlin, C.R., A.E. Tollefson, H.A. Brady, B.L. Hoffman, and W.S. Wold. 1989. Cell. 57:135-144; Shisler, J., C. Yang, B. Walter, C.F. Ware, and L.R. Gooding. 1997. J. Virol. 71:8299-8306). RIDalpha localizes to endocytic vesicles but is not homologous to Rab7 and is not catalytically active. We show that RIDalpha compensates for reduced Rab7 or dominant-negative (DN) Rab7(T22N) expression. In vitro, Cu(2+) binding to RIDalpha residues His75 and His76 facilitates the RILP interaction. Site-directed mutagenesis of these His residues results in the loss of RIDalpha-RILP interaction and RIDalpha activity in cells. Additionally, expression of the RILP DN C-terminal region hinders RIDalpha activity during an acute adenovirus infection. We conclude that RIDalpha coordinates recruitment of these GTP-Rab7 effectors to compartments that would ordinarily be perceived as early endosomes, thereby promoting the degradation of selected cargo.
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Affiliation(s)
- Ankur H Shah
- Department of Physiology and Biophysics, School of Medicine, Case Western Reserve University, Cleveland, OH 44106, USA
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15
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Jordens I, Westbroek W, Marsman M, Rocha N, Mommaas M, Huizing M, Lambert J, Naeyaert JM, Neefjes J. Rab7 and Rab27a control two motor protein activities involved in melanosomal transport. ACTA ACUST UNITED AC 2006; 19:412-23. [PMID: 16965270 DOI: 10.1111/j.1600-0749.2006.00329.x] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Melanosomes are lysosome-related organelles that synthesize, store and transport melanin. In epidermal melanocytes, melanosomes mature and are transferred to surrounding keratinocytes, which is essential for skin and coat colour. Mouse coat colour mutants reveal a critical role for the small GTPase Rab27a, which recruits myosin Va through its effector protein melanophilin/Slac2a. Here we have studied how two different Rab GTPases control two motor proteins during subsequent phases in transport of melanosomes. We show that the small GTPase Rab7 mainly associates with early and intermediate stage melanosomes and Rab27a to intermediate and mature melanosomes. Rab27a is found in an active state on mature melanosomes in the tips of the dendrites. The Rab7-Rab7-interacting lysosomal protein-dynein pathway only controls early and intermediate stage melanosomes because the mature melanosomes lack Rab7 and associate with the actin network through Rab27a recruited MyoVa. Thus two Rab proteins regulate two different motor proteins, thereby controlling complementary phases in melanosome biogenesis: Rab7 controls microtubule-mediated transport of early and Rab27a the subsequent actin-dependent transport of mature melanosomes.
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Affiliation(s)
- Ingrid Jordens
- Department of Tumour Biology, The Netherlands Cancer Institute, Amsterdam, The Netherlands
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16
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Soni LE, Warren CM, Bucci C, Orten DJ, Hasson T. The unconventional myosin-VIIa associates with lysosomes. ACTA ACUST UNITED AC 2005; 62:13-26. [PMID: 16001398 PMCID: PMC1201382 DOI: 10.1002/cm.20080] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Mutations in the myosin-VIIa (MYO7a) gene cause human Usher disease, characterized by hearing impairment and progressive retinal degeneration. In the retina, myosin-VIIa is highly expressed in the retinal pigment epithelium, where it plays a role in the positioning of melanosomes and other digestion organelles. Using a human cultured retinal pigmented epithelia cell line, ARPE-19, as a model system, we have found that a population of myosin-VIIa is associated with cathepsin D- and Rab7-positive lysosomes. Association of myosin-VIIa with lysosomes was Rab7 independent, as dominant negative and dominant active versions of Rab7 did not disrupt myosin-VIIa recruitment to lysosomes. Association of myosin-VIIa with lysosomes was also independent of the actin and microtubule cytoskeleton. Myosin-VIIa copurified with lysosomes on density gradients, and fractionation and extraction experiments suggested that it was tightly associated with the lysosome surface. These studies suggest that myosin-VIIa is a lysosome motor.
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Affiliation(s)
- Lily E. Soni
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093
| | - Carmen M. Warren
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093
| | - Cecilia Bucci
- Dipartimento di Scienze e Tecnologie Biologiche ed Ambientali, Universita degli Studi di Lecce, 73100 Lecce
| | - Dana J. Orten
- Center for Hereditary Communication Disorders, Boys Town National Research Hospital, 555 N. 30th Street, Omaha, NE 68131-9909
| | - Tama Hasson
- Section of Cell and Developmental Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, CA 92093
- Address correspondence to: Tama Hasson, Ph.D., University of California at San Diego, Division of Biological Sciences, Section of Cell and Developmental Biology, 2129 Bonner Hall, MC 0368, 9500 Gilman Drive, La Jolla, CA 92093-0368, Phone: 858-822-3033; Fax: 858-822-3034,
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17
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Nascimento AA, Roland JT, Gelfand VI. Pigment cells: a model for the study of organelle transport. Annu Rev Cell Dev Biol 2004; 19:469-91. [PMID: 14570578 DOI: 10.1146/annurev.cellbio.19.111401.092937] [Citation(s) in RCA: 130] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Eukaryotic organisms rely on intracellular transport to position organelles and other components within their cells. Pigment cells provide an excellent model to study organelle transport as they specialize in the translocation of pigment granules in response to defined chemical signals. Pigment cells of lower vertebrates have traditionally been used as a model for these studies because these cells transport pigment organelles in a highly coordinated fashion, are easily cultured and transfected, are ideal for microsurgery, and are good for biochemical experiments, including in vitro analysis of organelle motility. Many important properties of organelle transport, for example, the requirement of two cytoskeletal filaments (actin and microtubules), the motor proteins involved, and the mechanisms of their regulation and interactions, have been studied using pigment cells of lower vertebrates. Genetic studies of mouse melanocytes allowed the discovery of essential elements involved in organelle transport including the myosin-Va motor and its receptor and adaptor molecules on the organelle surface. Future studies of pigment cells will contribute to our understanding of issues such as the cooperation among multiple motor proteins and the mechanisms of regulation of microtubule motors.
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Affiliation(s)
- Alexandra A Nascimento
- Department of Cell and Structural Biology, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA.
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Setaluri V. The Melanosome: Dark Pigment Granule Shines Bright Light on Vesicle Biogenesis and More. J Invest Dermatol 2003; 121:650-60. [PMID: 14632178 DOI: 10.1046/j.1523-1747.2003.12500.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Vijayasaradhi Setaluri
- Department of Dermatology, Wake Forest University School of Medicine, Winston-Salem, North Carolina, USA
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Dooley TP, Curto EV, Davis RL, Grammatico P, Robinson ES, Wilborn TW. DNA microarrays and likelihood ratio bioinformatic methods: discovery of human melanocyte biomarkers. PIGMENT CELL RESEARCH 2003; 16:245-53. [PMID: 12753397 DOI: 10.1034/j.1600-0749.2003.00036.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
In this article, some of the advantages and limitations of DNA microarray technologies for gene expression profiling are summarized. As a model experiment, DermArray DNA microarrays were utilized to identify potential biomarkers of cultured normal human melanocytes in two different experimental comparisons. In the first case, melanocyte RNA was compared with vastly dissimilar non-melanocytic RNA samples of normal skin keratinocytes and fibroblasts. In the second case, melanocyte RNA was compared with a primary cutaneous melanoma line (MS7) and a metastatic melanoma cell line (SKMel-28). The alternative approaches provide dramatically different lists of 'normal melanocyte' biomarkers. The most robust biomarkers were identified using principal component analysis bioinformatic methods related to likelihood ratios. Only three of 25 robust biomarkers in the melanocyte-proximal study (i.e. melanocytes vs. melanoma cells) were coincidentally identified in the melanocyte-distal study (i.e. melanocytes vs. non-melanocytic cells). Selected up-regulated biomarkers of melanocytes (i.e. TRP-1, melan-A/MART-1, silver/Pmel17, and nidogen-2) were validated by qRT-PCR. Some of the melanocytic biomarkers identified here may be useful in molecular diagnostics, as potential molecular targets for drug discovery, and for understanding the biochemistry of melanocytic cells.
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Basrur V, Yang F, Kushimoto T, Higashimoto Y, Yasumoto KI, Valencia J, Muller J, Vieira WD, Watabe H, Shabanowitz J, Hearing VJ, Hunt DF, Appella E. Proteomic analysis of early melanosomes: identification of novel melanosomal proteins. J Proteome Res 2003; 2:69-79. [PMID: 12643545 DOI: 10.1021/pr025562r] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Melanin is a heterogeneous biopolymer produced only by specific cells termed melanocytes, which synthesize and deposit the pigment in specialized membrane-bound organelles known as melanosomes. Although melanosomes have been suspected of being closely related to lysosomes and platelets, the total number of melanosomal proteins is still unknown. Thus far, six melanosome-specific proteins have been identified, and the challenge is to characterize the complete proteome of the melanosome to further understand its mechanism of biogenesis. In this report, we used mass spectrometry and subcellular fractionation to identify protein components of early melanosomes. Using this approach, we have identified all 6 of the known melanosome-specific proteins, 56 proteins that are shared with other organelles, and confirmed the presence of 6 novel melanosomal proteins using western blotting and by immunohistochemistry.
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Affiliation(s)
- Venkatesha Basrur
- Laboratory of Cell Biology, National Cancer Institute, National Institutes of Health, Bethesda, Maryland 20892, USA
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Hirosaki K, Yamashita T, Wada I, Jin HY, Jimbow K. Tyrosinase and tyrosinase-related protein 1 require Rab7 for their intracellular transport. J Invest Dermatol 2002; 119:475-80. [PMID: 12190873 DOI: 10.1046/j.1523-1747.2002.01832.x] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
We have recently identified the association of Rab7 in melanosome biogenesis and proposed that Rab7 is involved in the transport of tyrosinase-related protein 1 from the trans-Golgi network to melanosomes, possibly passing through late-endosome-delineated compartments. In order to further investigate the requirement of Rab7-containing compartments for vesicular transport of tyrosinase family proteins, we expressed tyrosinase and tyrosinase-related protein by recombinant adenovirus and analyzed their localization in human amelanotic melanoma cells (SK-mel-24) in the presence or absence of a dominant-negative mutant of Rab7 (Rab7N125I). Co-infection of the recombinant adenoviruses carrying tyrosinase (Ad-HT) and TRP-1 (Ad-TRP-1) resulted in the enhancement of tyrosinase activity and melanin production compared to a single infection of Ad-HT. In the Ad-HT-infected SK-mel-24 cells many of the newly synthesized tyrosinase proteins were colocalized in lysosomal lgp85-positive granules of the entire cytoplasm, whereas in the presence of Rab7N125I the colocalization of tyrosinase and lgp85 proteins was decreased markedly in the distal area of the cytoplasm. In the Ad-TRP-1-infected SK-mel-24 cells, TRP-1, which is reported to be present exclusively in melanosomes, was detected throughout the cytoplasm, but not colocalized in prelysosomal (early endosomal) EEA-1 granules. In the presence of Rab7N125I, however, TRP-1 was retained in the EEA-1-positive granules. Our findings indicate that the dominant-negative mutant of Rab7 impairs vesicular transport of tyrosinase and TRP-1, suggesting that the transport of these melanogenic proteins from the trans-Golgi network to maturing melanosomes requires passage through endosome-delineated compartments.
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Affiliation(s)
- Kuninori Hirosaki
- Department of Dermatology and Department of Biochemistry (Section II), Sapporo Medical University School of Medicine, Chuo-ku, Sapporo, Japan
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García-Borrón JC, Solano F. Molecular anatomy of tyrosinase and its related proteins: beyond the histidine-bound metal catalytic center. PIGMENT CELL RESEARCH 2002; 15:162-73. [PMID: 12028580 DOI: 10.1034/j.1600-0749.2002.02012.x] [Citation(s) in RCA: 199] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
The structure of tyrosinase (Tyr) is reviewed from a double point of view. On the one hand, by comparison of all Tyr found throughout nature, from prokaryotic organisms to mammals and on the other, by comparison with the tyrosinase related proteins (Tyrps) that appeared late in evolution, and are only found in higher animals. Their structures are reviewed as a whole rather than focused on the histidine (His)-bound metal active site, which is the part of the molecule common to all these proteins. The availability of crystallographic data of hemocyanins and recently of sweet potato catechol oxidase has improved the model of the three-dimensional structure of the Tyr family. Accordingly, Tyr has a higher structural disorder than hemocyanins, particularly at the CuA site. The active site seems to be characterized by the formation of a hydrophobic pocket with a number of conserved aromatic residues sited close to the well-known His. Other regions specific of the mammalian enzymes, such as the cytosolic C-terminal tail, the cysteine clusters, and the N-glycosylation sequons, are also discussed. The complete understanding of the Tyr copper-binding domain and the characterization of the residues determinant of the relative substrate affinities of the Tyrps will improve the design of targeted mutagenesis experiments to understand the different catalytic capabilities of Tyr and Tyrps. This may assist future aims, from the design of more efficient bacterial Tyr for biotechnological applications to the design of inhibitors of undesirable fruit browning in vegetables or of color skin modulators in animals.
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Affiliation(s)
- José C García-Borrón
- Department of Biochemistry & Molecular Biology B & Immunology, School of Medicine, University of Murcia, Murcia, Spain
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Raposo G, Marks MS. The dark side of lysosome-related organelles: specialization of the endocytic pathway for melanosome biogenesis. Traffic 2002; 3:237-48. [PMID: 11929605 DOI: 10.1034/j.1600-0854.2002.030401.x] [Citation(s) in RCA: 124] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Melanosomes are lysosome-related organelles within which melanin pigments are synthesized and stored in melanocytes and retinal pigment epithelial cells. Early ultrastructural studies of pigment cells revealed that melanosomes consist of a complex series of organelles; more recently, these structures have been correlated with cargo constituents. By studying the fate of melanosomal and endosomal cargo in melanocytic cells, the effects of disease-related mutations on melanosomal morphology, and the genes affected by these mutations, we are beginning to gain novel insights into the biogenesis of these complex organelles and their relationship to the endocytic pathway. These insights demonstrate how specialized cells integrate unique and ubiquitous molecular mechanisms in subverting the endosomal system to generate cell-type specific structures and their associated functions. Further dissection of the melanosomal system will likely shed light not only on the biogenesis of lysosome-related organelles but also on general aspects of vesicular transport in the endosomal system.
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Affiliation(s)
- Graça Raposo
- UMR-144, Institut Curie, CNRS, Paris, Cedex 75005, France.
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Sharma S, Wagh S, Govindarajan R. Melanosomal proteins--role in melanin polymerization. PIGMENT CELL RESEARCH 2002; 15:127-33. [PMID: 11936270 DOI: 10.1034/j.1600-0749.2002.1o076.x] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Melanin, the major determinant of skin colour, is a tyrosine-based heteropolymer of indeterminate molecular weight. In vivo, melanin synthesis occurs within highly specialized organelles called melanosomes. Coated vesicles encapsulating the enzyme tyrosinase and tyrosinase related proteins, fuse with premelanosomes that contain structural proteins to form mature melanosomes. Coated vesicles and premelanosomes have been shown to have only melanin monomers but not the polymer. Our earlier results have clearly shown that the presence of proteins other than tyrosinase are critical for the post-tyrosinase steps of melanin polymerization at acidic pH. Proteins in melanosomes are difficult to purify because of their firm association with melanin. Thus, with progressive melanization, melanoproteins become progressively insoluble. In this paper, we discuss the isolation and purification of melanosomal proteins and their role in melanin polymerization. We have hypothesized that the initiation of polymerization and the binding of melanin to proteins are two discrete events and we have developed assays to quantify these events. Purified melanosomal proteins differ in their ability to polymerize melanin monomers. Further, we have also shown that two polypeptides (28 and 45 kDa) purified from melanosomes inhibit melanin polymerization but can bind preformed melanin. In conclusion, melanosomal proteins regulate melanin polymerization and differ in their ability to bind melanin. Polymerization and binding abilities of melanosomal proteins are specific to each protein and melanin-protein interaction is not nonspecific.
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